Note: your application will not be affected during the upgrade， but you can neither manage the cluster through the Web interface, nor use the Docker client to connect to the cluster’s access port for about 2 minutes.
The Agent of the Container Service is installed on each server in the cluster. It receives commands issued by the Container Service control system.
New functions are regularly added to the Container Service. If you need the latest functions, update the Agent of the cluster.
Log on to the Container Service console.
Click Clusters in the left-side navigation pane.
Select the desired cluster, click More > Upgrade Agent.
In the pop-up dialog box, click OK.